In general, when people unconsciously hold a container with a very hot substance such as coffee or ramyon, they may drop the container because the container is hot. Alternatively, it is difficult to hold very cold containers with one hand, so napkins, corrugated cardboards, or empty cups over the container are used, which is disadvantageous in terms of the manufacturing cost, reduction of wastes, and in terms of saving.
In order to solve these problems, a “Disposable Cup and Container” has been disclosed in Korean Patent Application Publication No. 10-2001-0077172.
Protrusions are formed at the portion of a cup or a container to be held with a hand to prevent heat from directly conducting from the substance in the cup or container to the portion to be held so that a user can hold the cup or container easily and long by hand regardless of the temperature of the substance.
However, since the protrusions are in contact with the outer side of a cup on its inner side, heat can transfer when the cup is used for a long time, and it is difficult to form the protrusions when manufacturing the cup, so the cup did not come into the market.
Korean Patent Application Publication No. 10-2001-0077172 (titled “Disposable Cup and Container”)